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Obsolete: This article refers to an aspect of the game which has been removed. It is retained for historical reference only.
Level 5
School1 Enchantments
Casting noise 0
Spell noise 0
This spell extends the duration of most beneficial enchantments affecting the caster.

Extension was a level 5 Enchantments spell which extended the duration of certain enchantments affecting the caster. It also had a 50% chance of causing one point of magic contamination (plus an extra guaranteed point if extending Haste or Invisibility).

You could not extend spells you hadn't memorized, or extend non-spell effects such as Might. The chance of extending a spell was 50% + the spell's success rate, meaning you could fail to extend spells with a spell success level of "Poor" or below.


Extension prolonged the following magical effects already affecting you as if you had just recast that enchantment at the same spell power as your Extension spell, with the exception of Ring of Flames and Condensation Shield.

100 turns maximum:

80 turns maximum:

  • Haste* (min 40, 100 turns maximum if wearing an amulet of resist slowing)

50 turns maximum (you will usually see the expiration messages of these):

30 turns maximum:

Extended only by a few turns:

For each of the asterisked effects that are prolonged, you gained one point of magic contamination instantly. This is in addition to the 50%-likely single point of magic contamination you might have incurred anyway AND the ongoing magic contamination due to Invisibility or Haste being in effect.

Extending Phase Shift was problematic because it has a cap of 30 and a warning about 5/6 turns before expiration, and Extension caused 0.5 glow, while you only lose 0.5 glow every 20 turns. At power 100, Extension would set the Phase Shift turns to about 25 on average. Thus, you had to wait some turns after the warning to extend, and even then, the thin margins often lead to mutagenic glow.

Extension could allow you to maintain any of Xom's enchantments as well, including his unique Stonemail spell.


You could use this spell to keep several effects on indefinitely without needing to repeatedly recast the individual spells. This saved time and MP in battle and while travelling, and was a general convenience to the player.

As an example, the following set could be sustained indefinitely, if you had the individual spells memorised:

Adding Necromutation obviates the need for Resist Poison and disables Stoneskin, and Regeneration:

Casting Necromutation will result in excommunication by good gods, and reliably extending it requires fairly high skill in Necromancy and Transmutation (15+). Its benefits more than offset its disadvantages, however.

Changing init.txt

To get the most out of Extension, you should change your game configuration to inform you when you need to recast the spell.

Add the following lines to your init.txt. They will cause the game to stop when your spell effects are about to expire.

travel_stop_message = duration:
force_more_message = duration:

travel_stop_message = You are starting to lose your buoyancy
force_more_message = You are starting to lose your buoyancy

travel_stop_message = You have a feeling this form
force_more_message = You have a feeling this form
message_colour = lightred:You have a feeling this form

travel_stop_message = Your transformation
force_more_message = Your transformation
message_colour = lightred:Your transformation

travel_stop_message = You feel uncertain
force_more_message = You feel uncertain

travel_stop_message = Your deflect missiles
force_more_message = Your deflect missiles

Then, adjust the extension spell to a letter you like (for instance 'z' so you tap 'zz') and/or add a macro for it.

After that, whenever you get a duration message, dismiss the --More-- prompt and cast Extension.

Occasionally a spell will only be extended for a few turns or even one turn, so if you get any kind of expiration message immediately after casting Extension, cast it again.

It is a good idea to wield a staff of enchantments when you are traveling or doing non-combat activities so that your extensions will last longer.

Extending Haste

It is possible to use Haste while also using Extension, although you do not want to cast Extension while you are hasted, as this will soon lead to mutagenic levels of magical contamination.

One way to safely combine the two spells is to cast Extension with a staff of enchantments wielded, ideally multiple times (so that your enchantments last more than 80 turns, the maximum of Haste). Then, cast then Haste itself (which will be in force for 40-80 turns). You may also want to wield a lantern of shadows, to increase the chances of Haste taking less than 50 turns, so that it expires before Ozocubu's Armour and Control Teleport.

A simpler method is to re-cast any individual spells that expire before Haste does; once Haste itself expires, you can safely cast Extension again if you are not already substantially contaminated.

Should you find yourself glowing as a result of accidentally extending Haste, make certain to not extend it again. An amulet of resist mutation will ward off mutation 90% of the time; if playing as an undead (or if necromutated), you will rot instead of mutating, which can be cured via the means outlined on the rot page.

If you want to turn invisible, use a ring of invisibility or cloak of darkness to turn visible when no longer needed.


Extension was removed in 0.8.